Sound signaling



y 1939- 1 F. VON VOIGTLANDER ,158,209

SOUND S IGNALING Filed Aug. 15, 1936 2 Sheets-Sheet l May 16, 1939.

F. VON VOIGTLAN DER SOUND SIGNALING Filed Aug. 15, 1936 2 Sheets-Sheet 2 4777mm WQQ mart/r Patented May 16, 1939 SOUND SIGNALING Frederick Von Voigtlander, Adrian, Mich., assignor to Schwarze Electric Company, Adrian, Mich, a corporation of Michigan Application August 15, 1936, Serial No. 96,285

1 Claim.

This invention relates to tone control and production.

This invention has utility when incorporated in electrically actuated horns, especially of the diaphragm type, equipped with elbow or whorl trumpet therefrom.

Referring to the drawings: Fig. 1 is a side view, with parts broken away, of an embodiment of the invention in a horn as for motor vehicles;

Fig. 2 is a view of the horn from the left of Fig. 1;

Fig. 3 is a medial section on an enlarged scale through the horn with a diiferent type of mounting;

Fig. 4 is a wiring diagram for the electrical actuator for the horn;

Fig. 5 is a view of the horn actuator apart from the housing;

Fig. 6 is a view of the actuator from the opposite side as to the showing in Fig. 5, with the diaphragm broken away;

Fig. '7 is a section on the line V,II[VII,v Fig. 5;

Fig. 8 is a section on the line VIII-VIII, Fig. 3;

Fig. 9 is a section on the line IXIX, Fig. '7;

Fig. 10 is a diagrammatic showing of the armamagnet core;

Fig. 11 is a view similar to Fig. 10, with the armature partially shifted at energizing cf the electromagnet; and

, Fig. 12 is a view of the armature in the fully thrown position, which is, in practice, not a striking or impact.

Bracket l is shown with eye 2, in which may be inserted bolt 3 through lock washer 4 to engage internally threaded portion 5 of projecting boss or stem 6, fixed with housing section I. This housing section I, in lieu of the boss 6, may be provided with boss 8 having externally threaded portion 9 for mounting. It is to be noted, with either the boss 6 (Figs. 1, 2) or the boss 8 (Fig. 3), the structure may be disposed in a desired angular relation. This housing section "I has rivet connection II] with complementary housing section II, centrally of which, concentric with the boss 8, is port I2 with elbow l3 therefrom in communication with flare or bell M for this first section H and bell portion l5 for the section I. In this complete bell portion I4, [5, there may be located screen IE to keep out foreign matter as insects. The general direction of this projector terminus or hell [4, I5, is radially from this port l2.

For low frequency projector, there is desired increase of duct distance between the port l2 and this bell l4, I5, over direct radial form, and such is herein effected by curved duct or whorl passage H. In practice,\ this passage I1 is definitely designed to coordinate with the frequency of the diaphragm of this device. To such end, the medial line or axis of this duct I! from the port l2 to the radial bell l4, I5, is generous at the more abrupt turn portions, but of an increasing cross section or area on a formula of k constant; yo equals area at small end or port [2; .1: equals axis or center line distance or length from the center of the port I2; and 1; equals the cross sectional area of this duct H; the equation being y y eflw) when e indicates the logarithmic function, in this exponential formula initially checked experimentally.

This curved duct I1 is completed by flange [8 from the section I, registering with opposing flange l9 from the section II with interlocking terminal groove and rib joint 20 more or less continuous therebetween. The sections 1, II, as assembled by the rivet I!) are effective in the complete duct assembly for this unit housing.

This housing section H has endless or annular seat 2|, against which may abut diaphragm 22 having peripheral notches 23 astride bolts 24 through flange 25 of actuator housing cup 26. This diaphragm 22 say of steel has centrally conical portion 21 terminating in flat central portion 28. Fiber washers 29 are on opposite sides of this portion 28, and there nest with washers 30 against the outer of which look washer 3i is held by nut 32 on threaded stem 33 say of steel having shoulder 34 opposing the inner washer 30.

The port l2 in the housing II is concentric with the diaphragm 22 and has about this mounting on the diaphragm for the stem 33, a flare 35 at approximately 40 from the plane of the diaphragm 22, toward at-rest position of the diaphragm 22, aproximately to the plane of the portion 28 of the diaphragm. From this portion the housing II has, opposing the conical portion 21 of the diaphragm 22, a flare or conical portion 36 of aproximately 10 from the plane of the diapragm 22 out to in excess of half the distance from the flare 35 toward the seat 2|. The latter portion of this section of the housing between the seat 2| and the conical tapered portion 36 is tapered portion 31 of approximately 2 away from the plane of the diaphragm 22. It is thus seen that between the diaphragm 22 and the housing ll there is provided chamber 38 of concentric annular cross' section increasing toward the port l2 in such dimension that throttling is not possible from diaphragm oscillation, but that in this oscillation with a height for the cone of the diaphragm of say .14 inch, its flexing from plane of rest or half-amplitude in operation would approximate .04 inch, with the total amplitude approximately .07 inch. This means that the performance hereunder is effective against restricting air flow in or out over shoulders 33, 39', between the flares 35, 3'6 and 31. This continuous dishing reactions are of practical worth in tonal value against disturbance of the frequency or undesired harmonics.

This housing 26 has, on the concave side thereof, anchored therewith by rivets 48 (Fig. 6) plates 4| holding therebetween laminations 42 as the core of the electromagnet, between the legs of which is mounted coil 43 having lead 44 therefrom to spring plate terminal 45. From this terminal 45, there extends lead 4'5 to resistor winding 4'! on insulation plate 48 mounted by rivets 49 fixed with the inside of this cup or housing 26. From this resistor 41 extends lead 50 to terminal connected to supply line 52, say of 6 volt direct current in the event the device is used in an automobile. The companion supply power line 53 for current extends to terminal 54 having connection by lead 55 to the opposite side of the coil 43.

On this plate terminal 45 is contact 56 opposed by adjustable contact 51 (Figs 4, 7) as a switch. The contact 57 is carried by bracket 58 mounted on the terminal 5| and is a by-pass for the resistance 41, which resistance 41, as in series with the coil 43, precludes full cutting out of the coil 43, and, therefrom of high frequencies or harmonics, avoids deleterious actions at the terminals between the contacts 5B, 51. Thisplate 45 extends toward the stem 33 and is accordingly laterally from the axis of the diaphragm 22.

Mounted on this stem 33 at threaded portion 59 is cup or concave bearing member 60 into which seats convex side SI of armature 62 having outward therefrom concave seat 63 entered by convex washer 64. Loading washers 65 space lock washer 66 from holding nut 61 in the adjusted position for this armature 62 as to electromagnet laminated core 42.

In the adjustment hereunder, the side 68 (Fig. of the armature 62 toward the contacts or switch 56, 57, is in closer proximity to the 1aminated core 42 than remote side 69. The resistance of the spring 45 retards the pull action of the energized electromagnet on the side 68,

thereby tending to flex the stem 33 as the armature 62 moves toward the laminated pole 42,

At the oscillation throw of the diaphragm 22, there is approximate parallelism between the armature 62 and the opposing faces of the laminated pole 43 with but slight clearance therebetween, say of the order of .005 inch. This uniform air gap throughout the effective area of the armature is a neutralizing of the resistance at the breakers or contacts 51, 58, contributing toward symmetrical flexing throughout for the diaphragm 22 against unequal disturbance therefrom in the oscillation periods, with tonal 'improvement therefrom.

The cup housing 26 for the actuator has openings 10 therein with which may be keyed arms H of U-shaped member rising to carry screw 12 centrally through dome 13 as a housing or closure for this actuator. Outer housing section as on the side of the resonant chamber 38 away from the housing section II provides a signal or horn exterior remote from the dome 13. Notwithstanding the progressive dimension for duct across section I? between the port [2 and the bell l4, 15, this housing section I provides a symmetrical exterior portion 14 (Fig. 1).

In the design herein disclosed, there is purpose in availing of the frequency of the diaphragm as to air as well as the frequency of the column of air in the projector therefrom, one to build up on the other in resonance apart from metallic sound or resonance due to any impact.

In practice, it'has been found that the mounting herein disclosed, located concentrically of the diaphragm, may be on such a vibrating structure as the motor block of an automobile propelled by an internal combustion engine. As so mounted concentrically of the diaphragm there is entire freedom from noise interference due to cross vibration. This means that the assembly for this signal may be rigid to this mounting.

What is claimed and it is desired to secure by Letters Patent is:

A signal device embodying a generally circular housing section having axially on one side a seat for mounting the section free to be positioned angularly in a desired direction range, said section having on the opposite side a spiral way toa radial projector, a second complementary housing section completing said spiral way and projector, said second section having axially thereof a port in co'mmunication'with said spiral way, said port being on the side of the second section away from the mounting seat, and a diaphragm actuator for the device carried by 'the second section and spaced by both sections from the mounting seat, said mounting seat being effective to position the projector in the said range of desired directions.

FREDERICK VON VOIGTLAN'DER. 

